Automatic grate for steam-boiler and other furnaces.



A. L. F. LEFEVRE.

AUTOMATIC GRATE FOR STEAM BOILER AND OTHER FURNACES.

APPLICATION FILED SEPT- II. 1916.

1,257,257. Patented Feb. 19,1918.

3 SHEETS-SHEET I A. L. F. LEFEVRE.

AUTOMATIC GRATE FOR STEAM BOILER AND OTHER FURNACES.

APPLlCATlON FILED SEPT. 1 x. 1916.

1,257,257. Patented Feb. 19,1918.

3 SHEETS-SHEET 2.

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AUTOMATIC GRATE FOR STEAM BOILER AND OTHER FURNACES.

' APPLICATION FILED SEPT. 11. 1916- 1 1,257,257. Patented Feb. 19, 1918.

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UNITED PATENT @FFTQE.

ARMANI) LEON FREDERIC LEFEVRE, OF ST.-DE1\TIS, FRANCE.

AUTOMATIC GRATE FOR STEAM-BOILER AND OTHER FURNACES.

Application filed September 11, 1916.

To aZZ whom it may concern:

Be it known that I, Annexe LEON FRED- nnro Lnrnvnn, a citizen of theRepublic of France, residing at 5 Rue du Jambon, St.- Denis, Seine,France, have invented new and useful Improvements in Automatic Gratesfor Steam-Boiler and other Furnaces, of which the following is aspecification.

The present invention relates to an arrangement of automatic grate,having a continuous or endless apron, for steam-boiler or otherfurnaces, and is designed to permit of operating either with air underpressure, (forced draft) while still leaving the front end of the apronin the open air, or to operate under natural draft by opening a doorprovided at the front.

For the regulation of the quantity of air necessary for combustion, theinvention proposes a special arrangement of movable dampers and movablesupporting rails there for, the rails being operated by certainexternally located connections and serving to regulate the position ofthe dampers.

In the accompanying drawing, which represents by way of example, purelyindicativcly and in no way limitatively, an automatic grate constructedaccording to the invention:

Figure 1 is a longitudinal section of the grate as a whole;

Fig. 2 is a transverse section along the line mm of Fig. 1, partlybroken away and on a larger scale.

Fig. 3 is a detail on a still larger scale.

The grate consists essentially of a movable endless apron a, formed bythe fire-bars proper a, mounted in their supports a connected togethertwo by two, and with them are combined the movable dampers Z). Thefire-bar supports a are fixed at each side of the grate to the actuatingchains C, which wind up, at the front and rear of the grate, on wheels0, 0 respectively, provided to receive them. The forward wheels 0 impartthe motion to the apron and with this end in view, the shaft 0 on whichthey are keyed, is actuated by any suitable mechanism (not shown) insuch a manner that the upper half of the apron a, constituting the grateproper, moves from front to rear, that is to say from left to right inFig. 1.

Between the wheels 0 and 0 the apron a is supported, either by slideways(such as d Fig. 2) or by antifriction rolls (2, fixed on Specificationof Letters Patent.

Patented Feb. 19, 1918.

Serial No. 119,536.

the sides or cheeks e of the frame of the apparatus.

The coal, introduced by any suitable means into the hopper f, falls,when the door 7 is opened, on to the front of the grate a which, in itsmovement from front to rear, takes with it a layer of coal, thethickness or height of which is determined by the position of the door7. The coal is consumed gradually as it moves toward the rear with theapron a and, as the latter begins to roll over the wheels 0 there onlyremains clinker on the grate, which then falls into an ash-pit providedto receive it.

The frame 6 of the apron a is mounted on.

four wheels 6, running on rails c of a special form. The lower portionsof the cheeks of the frame e engage in grooves e in said rails, so thatby means of a packing the passage of air can be arrested (Fig. 2).

A flexible sheet-metal plate 9, fitted at the rear, and a gate h placedat the front, render it impossible for the air introduced under thegrate, as shown by the arrows in Fig. 1, to take any other path thanthrough the layer of coal on the grate. Screens 2' and j rubbing gentlyagainst the apron a, complete the closure and prevent the passage of airanywhere except through the grate and the bed of coal thereon. When thedoor it is closed, as shown in Fig. 1, it is possible to operate withair under pressure, introduced beneath the grate (forced draft) whileleaving the apron a in the open air at the front. If the door h isopened by swinging it forward (from right to left in Fig. 1) one canoperate under natural draft.

The regulation of the quantity of air necessary to insure combustion iseffected as follows:

The dampers I) slide along two guide-rails, each of which is composed ofmovable sections k, is, hinged together at 70 The front section 70pivots by its front extremity at 70 on the frame and the rear section kis hinged by its rear extremity at 70 to a member 70 which in turnpivots lie on the rear of the frame. The rail-sections 76, 7c areprovided at their rear extremities with rolls 70 upon which two cams Z,Z are adapted to act so as to alter the position, as regards height, ofthe said rail-sections. With this in view, the cams Z, Z can be movedfrom front to rear (that is to say, from left to right in Fig. 1) andvice verse, by means of operating levers m keyed on a transverse shaftm, upon which there is also fixed, outside the frame 6, a lever arm m(Fig. 2) which can be acted upon by the intermediary of an actuating bar(not shown) operated from in front of the grate.

At the end 75 of the guide-rails, the dam per 5 always occupies theposition shown at I in Fig. 1, that is, a position in which it offersfree passage to the air, and, if the lever m occupies its extremeposition toward the left in Fig. l, the damper would retain its position1 until it arrives at the extremity 74 of the guide-rails. It will thenclose while traveling from 70 to 70 and will be completely closed(position 111) at this latter point.

lVhen the guide-rails occupy the position shown in Fig. 1, the dampersb, which are wide open from k to 7: will begin to close immediatelyafter having passed the point 70 they will then continue to closegradually as will be seen, for example, from position H) and will becompletely closed (position III) on reaching point 70 If the lever mwere pushed to its extreme right-hand position in Fig. 1, the dampers7), wide open at point 70*, would close gradua-lly from 70 to 7; andwould then remain closed while traveling from 70 to 70".

I claim:

1. An automatic grate for steam-boiler or other furnaces, comprising anendless movable apron, ii 'ebars carried by said apron, dampersassociated with said firebars and movable in the direction of theirheight to regulate the quantity of air passing through the grate, guidemeans upon which the dam pers along the upper run of the grate restduring the movement of the grate, said guide means being movable in thesame said direction as the dampers resting thereon for the purpose ofregulating the positions of said dampers, and means arranged under saidguide means for regulating the elevation thereof, said last named meansbeing movable in a plane at an angle to the plane of movement of theguide means and, in its movement and according to the degree anddirection thereof, varying the elevation of said guide means.

2. An automatic grate for steam-boiler or other furnaces comprising aframe, an end less apron movable in said frame, firebars carried by saidapron, dampers associated with said firebars and movable in the direction of their height to regulate the quantity of air passing throughthe grate, a guide rail upon which the dampers along the upper run ofthe grate rest during the movement of the grate, said guide rail beingin two parts hinged together and respectively movable in the same saiddirection as the dampers resting thereon, the front one of said partsbeing pivoted to the frame, a link pivoted to the rear part and to theframe,

and a means for adjusting the elevation of the parts of the guide railrelative to the firebars, thereby to effect adjustment of the positionsof the dampers resting and moving on said guide rail.

3. An automatic grate for steam-boiler and other furnaces comprising aframe, an endless apron movable in said frame, firebars carried by saidapron, dampers associated with said firebars and movable in thedirection of their height to regulate the quantity of air passingthrough the grate, a guide'rail upon which the dampers along the upperrun of the grate rest during move ments of the grate, said guide railbeing in two parts hinged together and movable in the same saiddirection as the dampers resting thereon, the front one of'said partsbeing pivoted to the frame, a link pivoted to the rear part and to theframe, a projection carried by each part of said guide rail, and a rodlocated between the runs of the grate and movable in a plane at an angleto the plane of movement of the guide rail, said rod having cam facesformed thereon to cooperate with said projections durmg the movement ofsaid rod in adjusting the elevation of the parts of the guide railrelative to the firebars and thereby adjusting the positions of thedampers resting and moving on said guide rail.

In witness whereof I have hereunto set my hand this 24th day of August,1916.

ARMANI) LEON FREDERIC LEFEVRE.

Witnesses R. H. BRANDON, CHAS. P. PRESSLY.

Gopies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. G.

